Maureen Jones has found a treasure. The metal detector enthusiast discovered a hammered silver coin dating to the time of William the Conqueror while searching a Gloucester field in November 2011. (photo)

For centuries, historians and scientists have bemoaned the loss of ancient technologies such as Greek fire and Damascus steel. In an article for io9.com, Alasdair Wilkins discusses both lost technologies, as well as the lost Apollo mission schematics.